Plus Therapeutics Inc. (NASDAQ:PSTV) saw its stock rise 8.4% in premarket trading Thursday after revealing that its subsidiary, CNSide Diagnostics, has signed a national coverage agreement with Humana Inc. (NYSE:HUM).
The agreement, which went into effect on October 29, 2025, extends insurance coverage for CNSide’s Cerebrospinal Fluid Tumor Cell Enumeration laboratory-developed test to roughly 16 million Humana members across the U.S. With this addition, total coverage for the diagnostic now reaches about 67 million people nationwide.
CNSide’s CSF Assay Platform is intended to enhance rapid diagnosis, monitor disease progression, and guide treatment decisions for patients with leptomeningeal metastases. The company notes that the platform has shown superior clinical value compared with current standards in nine peer-reviewed studies and the FORESEE clinical trial.
Since 2020, more than 11,000 CNSide tests have been administered across over 120 cancer centers in the U.S. The company highlights that the assay provides high sensitivity (92%) and specificity (95%) and influences clinical decision-making in 90% of cases.
The test continues to be offered exclusively through CNSide Diagnostics as a specialized service available to healthcare professionals nationwide.